The reasons for replacement and the age of failed restorations in general dental practice.

A cross-sectional survey among practitioners in Sweden treating adult patients was initiated to record the reasons for replacement of composite, amalgam, and glass ionomer restorations and to compare the findings with those obtained about 16 years ago. The age of the failed restorations was also recorded. The clinical diagnosis of secondary caries was the main reason for the replacement of all three types of restorations. The diagnosis was significantly higher for amalgam restorations than for composite and glass ionomer restorations. No statistically significant differences could be found in the diagnosis of secondary caries between composite and glass ionomer restorations. Major changes in the reasons for replacement of composite restorations were noted by comparing the present results with those from 16 years ago. A notable difference was seen with regard to a decrease in the relative frequency of replacements due to composite degradation/wear and an increase in the replacements due to bulk and marginal fractures. The reasons for replacement of amalgam restorations had remained much the same over the 16 years. The report that half the glass ionomer restorations replaced had the diagnosis secondary caries was by far the most surprising result. The age of the failed restorations were reported for a limited number of restorations. The median age was about 6 years for composite, almost 9 years for amalgam, and just more than 3 years for glass ionomer restorations.